I don't know about the Debka thing but the crash happened and Israel lost several commandos and the location was as stated. My understanding was that the terrain was much like the target area not because of a potential Air Route. But who knows for sure?
Why wouldn’t Israel just put a couple of subs in the gulf and launch a missile attack?
Besides Russian paranoia, the best explanation of this imho is that the Russians want to make it clear that they are basically annexing Georgian territory; it also is a palliative to the Iranians, who expected to have those S-300s by now.